Swivel attachment-plug



P. S. vMCLEAN.

SWIVEL ATTACHMENT PLUG.

APPLICATION FILED APfLz. 1911.

1 ,398,077. Patented Nov. 22, 1921.

, WITNESSES UNITED STATES PATENT QFFl',

PHILIP S. MCLEAN, OF BLOOMFIELD, NEW JERSEY,

iSSIGNOR, BY MESNE ASSIGN- IYIENTS, TO BENJAIIIN ELECTRIC MANUFACTURING COMPANY, 017' C ICAG'O, ILLL NDIS, A CORPORATION OF ILLINOIS.

Application filed April 25, 1917.

lanip sf cliet Without twisting;v the iieli the `plug is attached.

ie objects oi the invention is to orovide an iinprofed si'ivel attachment plug' hiade ot' a miniinuni nuinher ol siinple parts one Whieh is pir ieularl)v easy to asi' obje-et is to provide an improved '1 nlug, the hase portion oi? which lv attached Vto conductor Wires o' i and which when so attached re- /strain troni the point et attachl e cords aiu1 one in which the :i n; o'j the plug; niay be easilyY i `f h e nt requiring thatl tlieiT he :lirea led over the connuctor cords and Withc out requiring` the adjustment of any screws,

s holts or the like.

katl iti enilioi'liineiit ot the invention is shown 3,5 in the aceoinoanrinq drawings. rl`he Views of he drawings ire as loilows:

l i lhs-ure i is a separated View ol the plug',

ot the parte in assein- 'is a cross section et the plug asseinniliied plug, reiieral in insulatr.' tei'iiiinals 2 i to he niountls. an insulat- Cfr irsertion Within the screw the terininals Ytroni eaeh s ll and a center Contact G l ng spring i' carried by the l d to engage one ot the ter- Speceation of Letters laterit.

SWIVEL ATTACHMENT-PLUG.

Patented Nov. 22, i321.

sei-iai no. 164,519.

niinals to hohl the parts together and torni a center conti ct.

The insulating; hase l is 'toriiied oit any suitable insulating materialsneli as liber composition, hard rubbera porcelain or the like` prfteralily a inaterial which may be easily niolded. 'lhe exterior ot the base is shaped` to an;v desired contigui-ation to enable it to he readilyr grasped h v the lingers ot an operator. The top sur tace has a circula prefiection 8 which acts as a guide tor the rotatalilil .i will he explained in niore detA i llxtendine` axiall7 through th is an opening' S) of sullicient ceoninioilate insulated cone i six, to readilyv i ducter Horde. such as are usually attached to a iilugi' ol this character.

The electrical terminals and l are pi'e'l eralily eiiil Yililei1 ii i the hase at the tiine it is i iience in :nai utac-turing are in line xitli the pet'the opening El. Each terniinal an oli'set portion l() loriniig a shoulder for the i irpose ol" insuring' that the te niii als fill he held i i l iiiade and ior coni' their inside surta es riplierjv o xias l It is to he understood that tlnse te ininals iiiay be attached to an(VL carried hy the base in anjyv other suitable manner.

The teiininal has a lateral `projection ll which electrically engages the screw shell as will he later describen. th terminals are ot' approximately equal b their ends extend equal distances i'roni the urtace oit the hase and thea,7 are jrovided with openings l2 and i3 respectively, the bottoni surfaces ot which are equal distances Y.troni the hase. llacli teriiinal also earries binder sei-eus l-lf, the heads ot' wliielrare on the outer 'laces oi. the terminals.

By ineans of this construction, the conductor cords mayv be quickly and easilyv attached tothe hase, as illustrated in Fig. l. T-ires inaj: he cut oli' in equal lengths, stripped of insulation for equal distances i'froin their ends, passed through the opening 9 inthe base and through the openings l2 and 13 in the terminals and attached to the outer laces et the terminals by means ot the binder screws. Any withdrawal strains on the cord are taken up by the bottom edges of the ogenings l2 and 13 in the terminals, the cords having` a double right angle bend in passing from the point ot attachment over Viill in the hasta these bottom edges and out through the axial opening. The base may thus be very easily and quickly wired after which the remaining portions of the plug may be snapped into position.

The rotatable screw shell l is of the usual type and forms the outer contact of the plug engaging' the screw shell ot the lamp socket in which the plug is inserted. The shell is flanged about an insulating washer 15 so as to form an inwardly extending annular rib 16 and a shoulder 17. The annular' rib 16 tits around the circular projection 8 on the base so that the shell may be readily rotated and guided to prevent it from being displaced laterally. The shoulder 17 engages the projection 11 on the terminal 2 and thereby completes an electrical connection with the terminal which permits the shell to be rotated. rin insulating ring 18 surrounds the shell and abuts the ring 15 to prevent any ot the conducting parts projecting beyond the lamp socket when the plug is in circuit. This shell may be readily put in place over the terminals as will be clear by referring to Fig. 1, by simply tilting it to a slight angle to permit the rib 16 to be inserted under the projection 11 of the terminal 2, the distance between the terminal 8 and the opposite side of the rib being such as to readily permit the shell to be laterally displaced a` distance sutiicient to properly and easily position the shell. rThe shoulder 8, in addition to acting as a bearing shoulder tor the screw shell, prevents the insertion ot a wire or other instrument into the interior oit the plug between the shell and base.

The insulating spacer or filler 5 is formed ot suitable insulating material, such as *fiber composition, hard rubber, porcelain and the like, and is shaped to tit within the screw shell to insulate the terminals trom the shell and from each other. The outer end or Vtip ot the spacer is preferably rounded to facilitate the insertion ot a plug in a socket. The end ot the Vfiller which is inserted in the screw shell is provided with two recesses 19 and 2O of suitable size and shape to receive the terminals 2 and 8 with the conductor cords attached thereto. The outer walls 21 and 22 of the recesses insulate the terminals from the screw shell and the dividing wall 23 extending between the recesses insulates the terminals 'from each other. Y

The recesses 19 and 2O communicate with sockets 24 and 25 in which the ends ot the terminals 2 and 3 seat so that when the spacer is placed in position the bottoms of these sockets contact with the tops of the terminals and prevent the spacer being forced down to tightly grip the shoulder 17 on the screw shell and prevent'its turning. The lengthot the spacer is such that when the terminals engage the bottoms ot the sockets 24 and 25, the 'bottom surfaces oit the spacer contact the shoulder 17 with sutlicient clearance to enable the shell .to be readily rotated and at the same time to be held in position. rlhe side wall 21 has a slot 26 therethrough to accommodate the lateral projection 11 on terminal 2.

The center cont-act 6 comprises a suitable screw engaging a nut 2?, preferably embedded in the spacer 5. 'l he spring 7 is held beneath the head ot the center contact screw 6 and projects through an opening 28 in the spacer, thelower or free end of thespring being provided with a shoulder 29 which, when the plug is assembled, lies beneath the top edge ot the opening 13 in the terminal 3 and. electrically connects the center contact with this terminal and at the same time holds the parts together. rlhis construction permits the insulating spacer to be readily inserted into the screw shell and automatically locked into position without the insertion ot any screws or the tightening ot any nuts or bolts. lt it is desired to remove the spacer and disassemble the plug a small instrument may be inserted in the opening 28 to release the shoulder 29 from the terminal 3. l l

An exceedingly simple, inexpensive and efficient swivel attachment plug is accordingly provided, the base of which may be easily attached to conductor cores ol equal length and the remaining parts of the plug subsequently assembled on the base by simply inserting them in position and without manipulating any screws, nuts or bolts. The plug may be equally as easily talren apart yby simply pushing the spring 7 over and removing the spacer and the screw shell, after which the terminals are readily accessible. p

lt is to be understood that the structure shown is for purposes ot illustration only and that various changes may be made therein without departing `from the spirit and scope of the appended claims.

lll/*hat l claim is:

1. A swivel attachment plug comprising an insulating base having an opening therethrough for the passage ot conductor cords, electrical terminals carried )y said base and projecting substantially equal distances therevtrom, a screw shell mounted to rotate about vsaid terminals in electrical engagement with one ot them, an insulating spacer adapted to be inserted within the shell to rotatably hold the same in place and engaging the ends of the terminals to prevent the spacer binding the shell against rotation, and means carried by the spacer electrically connected to the other terminal for holding the parts together and forming a center contact.

2. fin attachment plug having' an insulating base provided with an opening for the standino` Contact on the base nroiectinw outb L .l l5

ivardly beyond said bearing shoulder, a

scr v shell haring an inwardly projecting cont-act shoulder engageable beneath the outstanding contact by movement ot the shell in tilted relation over said contact and lateral shifting of the shell to carry said contact shoulder beneath the outstanding contact, said shell having a bearing portion engageable over the bearing shoulder on the base upon the straightening oi the shell on the base, whereby said bearing shoulder holds the screw shell stviveled on the base with its contact llange engaged beneath the outstanding contact on the base, an insulating spacer detachably secured to the base and holding the screw shell against such tilting on the base as would tree it from the bearing shoulder, an end contact and terminals on the base Within the screw shell electrically connected with the end Contact and the outstanding contact aforesaid.

9. An attachmei plug comprising an insulating base having a cord passage and provided With a bearing shoulder, an outstanding contact on the base projecting Voutwardly beyond said bearing shoulder, a screw shell having an inwardly 'projecting contact shoulder enga geable beneath the outstanding contact by movement oit' the shell in tilted relation over said coiitact lateral shitting oit the shell to carry said Contact shoulder beneath the outstanding Contact, said shell having a bearing portion engageable over the bearing shoulder on the base by the straightening oi the shell on the base, whereby said bearing shoulder holds the screw shell siviveled on the base With its Contact liangeengaged beneath the contact on the base, an insulating spacer engaging the screu7 shell and holding it` against such tilting movement on the base as would free it irom the bearing shoulder, means tor detachably securing said rinsulating spacer to the base, a spring catch yieldingly securing said spacing member to the base, an end contact, and terminals on the base within the screw shell electrically connected with the end contact and the outstanding Contact atoresaid. Y

10. An attachment plug comprising a base, a sliding` contact member on the base., a screw shell in sliding engagement with said Contact, a spacing and guiding member engaging said screw shell and holdingA the saine in sliding engagement with the contact member, a yielding spring catch detachably securing said positioning and guiding member to the base, an end Contact and terminals on the base electrically connected with said end contact and the sliding coiitact.

ll. Ain attachment plug comprising a base having a cord passage and provided with a bearing shoulder, an outstanding con-v tact on the base projecting outwardly beyond said bearing shoulder, a screw shell having an inwardly projecting contact shoulder engageable beneath the outstanding contact by the movement of the shell in tilted relation over said contact and the lateral shi-l ting ot the shell to carry said contact shoulder beneath the outstanding contact, said shell having a bearing portion engageable over the bearing shoulder on the base by the straightening ot the shell on the base, whereby said bearing shoulder holds the screw shell swiveled on the base with its contact iiange engaged beneath the outstanding Contact on the base, a spacer detachably secured to the base and having a liding tit Within the end of the screw shell to thereby hold the screw shell against such tilting movement on the base as would tree it i.. om the bearing shoulder, an end Contact and terminals on the base Within the screvir shell electrically connected with the end contaet and the outstanding Contact aforesaid.

'An attachment plug comprising an insulating base haif'ing a cord passage and provided with a bearing shoulder, a screw shell siriyeled at the base on said bearing shoulder and provided at said base portion with an inwardly projecting contact shoulder, contact on the insulating base engaging over said contact shoulder, an insulating spacing member detacliably secured to the insulating base having an abutment shoulder overstanding the contact shoulder on the screw shell, an end contact and terminals on the insulating base Within the screuT shell electrically connected With the end contact and the contacton the insulating base.

13, ein attachment plug comprising a base having a cord passage, projecting terminals on said base provided with openings therein all'ording strain reliefs 'for Wires passed therethrough,` a sivivcled'screu7 shell on the base, a spacing member engaged on the'projecting terminals, an end Contact on said spacing member, a spring catch electrically connected with said end contact and pro vided with a shoulder adapted to snap into the opening in one oix the terminals and sliding connections between the other terminal and the screw shell.

le. A swivel attachment plug having an insulating base provided with an openingtheretlirough 'for the passage of conductor cords, electrical terminals carried by said base and projecting therefrom, an insulating spacer, a screw shell rotatably mounted between the base and spacer and arranged to electrically engage one of the terminals, means carried by the spacer for releasably 

